Interview with physicist Gaetano De Luca: L'Aquila could have been saved
(17:32)

Once upon a time, heretics were burned at the stake, as occurred in the case of Giordano Bruno and Girolamo Savonarola. In Italy today, the heretics are those that speak the truth. They are no longer burned in the square, but get taken to court, deprived of any right to an investigation and intimidated. This does not only happens to the judiciary, but to anyone who dares to question the official version of events. Backed up with the data from an earthquake monitoring system, Physicist Gaetano Di Luca warned that an imminent earthquake was threatening the buildings in the town of L'Aquila. He asked that the local schools and the Student’s House be made safe. First he was officially challenged, then he was removed and the earthquake detection network was dismantled.

Summary:
1996, the initial warning
Magnitude amplified under the L'Aquila town centre
10 lost years

1996, the initial warning

De Luca: "My name is Gaetano De Luca and I’m a physicist who graduated back in ’91. Straight after getting my degree, I went into the field of experimental seismology. In ’91 I began to design and create local earthquake monitoring networks. The very first earthquake monitoring station I created, still at regional level, was set up at the end of ’91.
My story began in ’96, after a magnitude-4 earthquake struck the area around Amatrice and Montereale on the 20th October 1996. The earthquake was recorded in the historical town centre of Aquila, where certain instruments were located, accelerometers. These are stations that measure the rate of ground acceleration, and this is where a very strange thing occurred, namely that the recording displayed a tail effect. It’s not difficult to see on the image (see the video), in essence that was the earthquake. We can see the earthquake’s approach, or in other words the highest wave, namely wave "S", but what there shouldn’t have been was that tail effect, a kind of low-frequency resonance that continues for tens and tens of seconds.
My first reaction at the time was to think: “Oh my god, this instrument is broken and it is unable to damp the free oscillations”. I was convinced of this, I swear to you that I was convinced that the instrument needed to be checked and recalibrated or reset, but I was wrong. I was wrong in that the instrument was working perfectly and the tail effect that was making the historical town centre of l’Aquila resonate for tens and tens of seconds was an actual event. We obviously continued to take readings over a distance of easily thirty kilometres. This was at the end of ’96. Alarmed (at the time, I was working together with a number of colleagues from the former National Seismology Services), we decided to improve the measuring by adding more instruments..."
Blog: "So you discovered a ground reaction in the area of l’Aquila.."

Magnitude amplified under the L'Aquila town centre

De Luca: "The historical town centre. "
Blog: "The historical town centre, which no one had previously realised was happening?"
De Luca: "Technically speaking, this is evidence of local amplification and it is not based solely on this earthquake. We continued our work throughout ‘97, ‘98 and ‘99, years worth of work involving various types of measurements, including the measurement of background noise, but still focusing on the historical town centre, which ended in a scientific conclusion, namely that there was an amplification factor of almost 10 times."
Blog: "This means that, for any given earthquake, the ground under the historical town centre of l’Aquila reacts very differently to that in other areas located just a few kilometres away?"
De Luca: "Yes, in other words, if a village built on a rock would register a magnitude-6.3 earthquake, then the historical town centre of l’Aquila, with its amplification factor of 10, would register a magnitude equivalent to 6.7."
Blog: "So the amount of damage grows exponentially with any increase in the recorded magnitude, a figure that is...."
De Luca: "No, the magnitude is a logarithmic scale, so we must be careful. Multiplying by a factor of ten does not simply mean that if the magnitude is 6, that it suddenly becomes 60, obviously. It is a logarithmic scale and the calculation is somewhat more complex than that."
Blog: "Does this mean that the earthquake that struck San Giuliano on the 6th April solicited a different reaction to that of the historical centre of l’Aquila?"
De Luca: "Certainly. Many people are aware that the damage, the major damage is linked to the local amplification. Just think of Onna. Onna was virtually pulverised, however, Onna was originally built on sediment. Very close to Onna, however, literally a few hundred metres from Onna, there is a little village called Monticchio, which was originally built on bedrock and suffered some serious damage but was not completely pulverised like Onna was, and they were only a few hundred metres apart from one another, very close indeed, except that Onna stood on a plateau while Monticchio stands on bedrock. This is a typical effect caused, not by the earthquake, but by the type of ground. In ‘99, after years of work (we had also published some articles in the interim), we decided to reveal these findings at a press conference, but what I also wanted to say was that there was no need to panic. All I wanted to do was to throw a stone without hiding my hand because there was a potential solution. We still have a collection of press clippings from that time, the 25th….. "
Blog: "These are the articles that were written according to your…?"
De Luca: "Yes. The press conference was held on the 24th. We had a major problem at the time in that the earthquake risk was high, but we already knew that the central Apennine region around l’Aquila was at high risk of being struck by earthquakes, to which was now added the problem of amplification. But be careful: the idea was: "Lets start by making safe whatever we can, one building per year, or two perhaps, I don’t know, whatever we can, the sooner we start the sooner the job will get done". There was no way for us to know at the time that ten years later there would have been such a violent shock, because it could equally have occurred another ten years later."
Blog: "This issue of the town being at high risk of earthquakes, was this not a new revelation?"
De Luca: "No, it was common knowledge, but what was not yet common knowledge at the time was this matter of the amplification factor of 10 ... precisely. So the risk to the town was even greater."
Blog: "Was this initiative of yours not very well received?"
De Luca: "No, because that same day – and I can show you the letterhead later – you see, it’s dated the 25th November? On the very same day that the newspapers published the articles, the people in Rome were already drafting this letter, and it is common knowledge in l’Aquila, so in ‘99.."
Blog: "The purpose of the letter being to challenge what you had said?"
De Luca: "Yes, to challenge."
Blog: "A direct challenge against Dr.Gaetano De Luca."
De Luca: "Precisely. Obviously the director did not understand a word of what I was actually saying, because he even talks about certain statements regarding the seismicity of the area, even though I never mentioned anything about the seismicity of the area. What I did talk about, however, was a totally different issue, so obviously there was also a lot of ...precisely, and another thing.. when the director of a seismological service comes out with a letter such as this, it can only mean one of two things, namely, either he is abysmally ignorant, or he certainly had not taken the trouble to read … "
Blog: "In essence then, this letter states that Dr.Gaetano De Luca was not authorised to issue any statements. "
De Luca: "But I was authorised to do so and, above all, I was talking about something that had already been published. What is even more absurd is that he was telling me to retract what I had said. How could I be expected to retract something that had already been published at scientific level? This really is an aberration! I obviously responded to this letter, however, I never had the pleasure of any reaction to my response, or to this challenge for that matter, because I took their challenge point-by-point and responded to each of them in turn. However, I was essentially.."
Blog: "So the challenge was not based on merit and they never claimed that the amplification theory was nonsense?"
De Luca: "No, absolutely not. All there is is this letter and my detailed responses, which have never been acknowledged, but the fact remains that I was forced to leave. I struggled on until 2002, after the Molise earthquake, when the Abruzzo Regional network was dismantled, which was clearly done out of spite."
Blog: "What do you mean when you say that it was “dismantled”?"
De Luca: "The instruments were decommissioned and put into storage."
Blog: "Back in 2002?"
De Luca: "Yes. As a matter of fact, there is a large chunk of missing data, if you will, on the Abruzzo area from the end of 2002 through to 2005, in other words for 2003 and 2004, so let’s say, two and a half years in which no local monitoring was done."
Blog: "Whose decision was it to dismantle the regional network? "
De Luca: "The National Seismological Service."

10 lost years

Blog: "The question now is as follows. Ten years down the line, have the findings of the amplification study ever been officially disproven on merit?"
De Luca: "No! I continued to work on this data until August 2005, when I published the evidence in an article in one of the world’s most influential magazines in this field, namely the American Seismological Society Bulletin. Although it is in English, it is a simple matter to translate the article and stands as proof of the low-frequency amplification in the historic town centre of l’Aquila, using a multi-disciplinary approach. The work that was done is highly complex because we used a variety of data relating to different earthquakes both nearby and further away, different instruments and, as I said before, different earthquakes, also utilising background noise, and various technologies to eventually create models. What emerged at the end of all this work was confirmation of a frequency amplification in that very specific frequency range, amounting to an amplification factor approaching 10 times."
Blog: "So, notwithstanding these amazing revelations, they still chose to ignore you?"
De Luca: "No, it gets even worse. There was not even…… the fact remains that I was sidelined because of this press conference, literally sidelined."
Blog: "But did it clash with.. "
De Luca: "I don’t know, I have no idea what it clashed with. Quite honestly, I still ask myself to this day why I was so forcefully challenged."
Blog: "Is it impossible to predict earthquakes.. "
De Luca: "Absolutely."
Blog: "However, buildings can be made safe."
De Luca: "That is the idea. Bloody hell, we have a problem, the entire historical town centre resonates, it’s a specific peculiarity, now there’s a serious aggravating factor, so let’s start making safe whatever we can, like the schools for example. Back in ’99, there were a couple of schools, a few public buildings and the Student’s House. We are talking about some relatively minor interventions that were perhaps an important issue in terms of funding, but that did not require any major immediate funding. It would have been enough to tackle one building per year and, over a period of ten years, we could have sorted out at least ten buildings."
Blog: "The regulations that were in force already back in 1999, and those in force in 2005, the year in which you published your findings, and in 2009, the year of the actual earthquake, did they ever take the amplification factor into account?"
De Luca: "No, absolutely not, and here is an example: let me show you this picture (see the video) drawn by my dear friend , Engineer Giovanni Bongiovanni. Without going into any technical detail, I would like to point out the following. These very simple curves, the green one and the purple one, essentially reflect the regulations. The regulations applicable to the area of l’Aquila are category 2 regulations, which envisage construction on solid ground and on so-called “Su” ground, while the purple line reflects, let’s say, construction on sediment. These were the regulations applicable to the construction of buildings. What you see here is the 6th April earthquake, so the factor ten amplification went totally off the scale at this time."
Blog: "Does this mean that the regulations provide for a strength factor for houses that is less than half..."
De Luca: "Of what actually occurred."
Blog: "And they don’t appear to have any intention of include this parameter?"
De Luca: "I don’t know. I am not a seismic engineer so I don’t know and, in any event, I am not an experts as regards the regulations because I have little to do with them, however, what I know for sure is that it is not compulsory to adopt seismic micro-zoning measures prior to building houses, in other words, if I’m not mistaken all that is required is a survey.. a geological report, but this is an end unto itself, certain measures must be adopted. Taking into account that, as regards the category two regulations, although it is not even included in the category one regulations, there is this very real spectre of a magnitude 6.3 earthquake striking the historical town centre, if you want to build anything in the town centre itself then you had better go well beyond the existing regulations."
Blog: "Our readers may not really understand this, but the difference is astonishing, the gap that exists between where the regulations end and where the effects of an earthquake begin."
De Luca: "Precisely. This is in terms of movement, this scale is in centimetres (see the video), okay, so these are the movement forecasts relating to the periods when the respective regulations were in force."
Blog: "In closing, let me ask you this question: as someone from the L’Aquila region and as someone who studies earthquakes, how do you feel when you see that such a devastating factor is not taken into account and is indeed totally ignored?"
De Luca: "Only great bitterness. I have still not found answers to my questions, such as why this has happened to me and why I was challenged, I don’t know."
Blog: "At this point, even if it were by another researcher, the important issue us that this factor must be taken into account."
De Luca: "Yes, but unfortunately I believe that this is something that is destined to re-occur in other towns and when the next earthquake comes, we are likely to see the same thing happening again."